Department of Chemistry, The University of Hong Kong, Hong Kong, 999077, China.
Adv Mater. 2017 Aug;29(30). doi: 10.1002/adma.201701451. Epub 2017 Jun 9.
Over the last decades, scientists have endeavored to develop nanoscopic machines and envisioned that these tiny machines could be exploited in biomedical applications and novel material fabrication. Here, a visible-/near-infrared light-driven nanomotor based on a single silicon nanowire is reported. The silicon nanomotor harvests energy from light and propels itself by the self-electrophoresis mechanism. Due to the high efficiency, the silicon nanowire can be readily driven by visible and near-infrared illumination at ultralow light intensity (≈3 mW cm ). The experimental study and numerical simulation also show that the detailed structure around the concentrated reaction center determines the migration behavior of the nanomotor. Importantly, due to the optical resonance inside the silicon nanowire, the spectral response of the nanowire-based nanomotor can be readily modulated by the nanowire's diameter. Compared to other methods, light controlling potentially offers more freedom and flexibility, as light can be modulated not only with its intensity and direction, but also with the frequency and polarities. This nanowire motor demonstrates a step forward to harness the advantages of light, which opens up new opportunities for the realization of many novel functions such as multiple channels communication to nanorobots and controllable self-assembly.
在过去的几十年中，科学家们一直致力于开发纳米级机器，并设想这些微型机器可以应用于生物医学和新型材料制造领域。在此，我们报道了一种基于单根硅纳米线的可见光/近红外光驱动纳米马达。该硅纳米马达通过自电泳机制从光中获取能量并推动自身运动。由于效率很高，硅纳米线可以很容易地在超低光强（约 3 mW cm ）下被可见光和近红外光驱动。实验研究和数值模拟还表明，集中反应中心周围的详细结构决定了纳米马达的迁移行为。重要的是，由于硅纳米线内部的光学共振，纳米线基纳米马达的光谱响应可以很容易地通过纳米线的直径来调制。与其他方法相比，光控制具有更大的自由度和灵活性，因为光不仅可以通过其强度和方向进行调制，还可以通过频率和极性进行调制。这种纳米线马达展示了利用光的优势向前迈进了一步，为实现许多新功能（如纳米机器人的多通道通信和可控自组装）开辟了新的机会。
